Bart Hughes has a pretty good life, a beautiful wife, a young son, a good job with promotion prospects, and a renovated brownstone in New York. When wife and kid leave for a vacation, Bart stays behind to work on a project that will earn him that promotion, unaware that a certain inhabitant of his basement has other plans for his time. Bart goes a bit bonkers trying to kill this rat, destroying most of his house in the process. Certain allegorical elements tie the household conflict to the "rat race" in his office, but the main event is certainly the night-and-day contest of wills between man and rodent. 巴特（Peter Weller饰）拥有一个非常完美的生活：他有一位漂亮的妻子，可爱的孩子，一份前途光明的工作，生活于纽约的上流社会。然而，就在他的妻子和儿子外出度假的时候，家里却来了不速之客。一个晚上，巴特正呆在家中工作，这是一个将会给自己带来升迁的重要计划，他专著于工作中，却完全不知自家地下室里的一位“住客”还有另外的计划，这恐怕要占用他不少的时间。终于，一场人鼠大战来开帷幕，巴特几尽疯狂的要杀死这只老鼠，他几乎毁掉了自己的房子。他被这只老鼠折磨得丧失了原有的朝气，甚至在上班的时候也神情涣散，这场白天黑夜永不停息的战争到底什么时候才有一个了断呢？
